looking for advice for my BIL who is about to seperate

NYBoston05

My BIL is about to seperate from his wife.  They have 2 young boys.  He's the active care taker of these kids- and always has been.  I'm trying to be supportive and have said I think you should go talk to a lawyer.  How does it work if he wants to get primary custody and stay in the family house?  She's telling him to leave.  She works at night at a bar so on a normal day she's gone from 4pm-2am.  Then add in the late night drinks afterwork and she's not coming home at all some nights.  I know most people on this board are hard working single Moms but I was hoping maybe some advice for a Dad would be available....